Motor-controlled automobile radio antenna



May 24, 1960 J. B. cl-:JKA

MOTOR-CONTROLLEO AUTOMOBILE RADIO ANTENNA 3 Sheets-Sheet 1 Filed June13, 1956 INVENTOR May 24, 1960 J. B. cEJKA 2,938,207

MOTOR/-CONTROLLED AUTOMOBILE RADIO ANTENNA 3 Sheets-Sheet 2 Filed June13, 1956 CML-s, HMS 1 (VMM ATTORNEYS luf May 24, 1960 J. B. CEJKAMOTOR-CONTROLLED AUTOMOBILE RADIO ANTENNA Filed June 13, 1956 3Sheets-Sheet 3 FIG. 8.

FIG. 7.

FIG. 9,

lNvENToR L/05EPH E CEV/(f4 BY @An-Lis Hmm/SAIT@ ATTORNEYS United StatesPatent MOTOR-CONTROLLED AUTOMOBILE RADIO ANTENNA Joseph B. Cejka,Highland Park, NJ., assignor to General Bronze Corporation, Garden City,N.Y., a corporation of New York Filed June 13, 1956, Ser. No. 591,115

1 Claim'. (Cl. 343-714) This invention relates to collapsible whip-typeradio antennas for automobiles and other vehicles, and particuthoughrelatively simple and inexpensive in construction.

It is a further object to provide such an antenna wherein there is apositive driving engagement with the cable whereby slippage at thispoint is eliminated and wherein the cable is -engaged along aconsiderable portion of its length to distribute the strain imposed onthe cable and thereby reduce the possibility of cable failure. Anotherobject is that of providing in such an antenna facilities for storingand guiding the cable of such construction that the cable may be drivenin either direction without appreciable hazard of binding, kinking orjamming. Other and further objects will be in part specically pointedout and in part apparent from the ensuing description.

In the drawings:

Figure l is a side elevational view of an antenna embodying features ofthe present invention with the antenna, with the length of the antennareduced by showing it broken at several points and with it shown partlyin vertical section.

Figure 2 is a greatly enlarged fragmentary side elevational view of thehousing at the lower end of the antenna of Figure l, with the housingbeing shown partly in vertical section.

Figure 3 is a fragmentary vertical sectional view of a portion of themechanism shown in Figure 2.

Figure 4 isa somewhat diagrammatic elevational view of the gear train ofthe mechanism shown in Figure 2.

Figure 5 is an exploded view of the cable driving, guiding and storingcomponents of the mechanism shown in Figure 2, shown at a scale slightlyreduced relative to that of Figure 2.

Figure 6 is a schematic diagram of the electrical control circuit oftheantenna.

Figure 7 is a side elevational view of the upper portion of the antenna,`at the approximate scale of'Figure 2, with the antenna shown partiallybroken away to reveal its inner construction.

Figure 8 is an isometric view ofthe switch-operating cam of themechanism shown' in Figure 2.

Figure 9 is an end elevational view of the cam shown in Figure 8.

As may be seen in Figure l, the antenna generally comprises a whipportion 10, a mounting base 12, a tubular extension 14, an electricmotor 16 and a housing 18 which contains the driving mechanismassociated with the motor 16 and the facilities for guiding and storingthe exible cable, as well as the cam-operated limit switches whichcontrol the'rnotor.I

2,938,207 Patented May 24, 1960 As may be seen in Figure 7, the whipportion of the antenna comprises four sections, a ixed outer tubularsection 20, intermediate tubular telescoping sections 22 and 24, and aninnermost section 26 of flexible solid rod. Each of the inner sections22, 24 and 26 is longitudinally slidable relative to the adjacent outersection. The two intermediate sections 22 and 24 are provided at theirlower ends with external collars 28 which engage internalcircumferential beaded ribs which are swaged in the adjacent outersections near their lower ends to limit the downward movement of thesections 22 and 24. Their upward movement is limited by engagement ofthe collars 2S with similar beadings'32 near the upper ends of theadjacent outer sections. Downward movement of the innermostsection 26 islimited by engagement of a iinial or tip 34 xed at its upper end withthe upper end of the adjacent section 24. Upward movement of theinnermost section 26 is limited by engagement between the beading 32near the upper end of the adjacent section 24 and the ferrule 36 bywhich the lower end of the innermost section 34 is spliced to the upperend of the flexible cable 38.

The flexible cable 38 is formed of two helically wound steelsprings,'the smaller of which forms the core of the cable and the largerof which is wrapped tightly around the smaller with the turns of thelarger held in spaced relation to each other by engagement with theturns of the inner spring so that they are capable of functioning asrack teeth.

The outermost section 20 of the antenna is xedly supported in insulatedrelation to the base 12 by a plastic sleeve 40. rThe base 12 extendsthrough an opening 42a in the -automobile body 42 and is secured iniixed posi- Ytion relative thereto by a pair of toggle members 44 vtion12a of the base 1'2 and bears downwardly against a generallyhemispherical insulator 48 which in turn bears` against a rubber washer5t) which is interposed between it'and the outer surface of theautomobile body 42. The pivotal mounting of the 'toggle members 44 andthe wedge shape of the slot 48a in the hemispherical insulator 48through which the base '12 passes (see Figure 1) permits the antenna tobe mounted in a vertical position although vthe adjacent portion of theautomobile body 42 may be inclined at a considerable angle with respectto the horizontal.

Extending downwardly from the base 12 is an extension tube 14 whichreceives the sections of the antenna whip when they are in theirretracted position, in which they are shown in Figure 7. The upper endof the tubular extension r14 is received in the lower end ofthe base 12and is secured thereto by screws 54 (Figures l and 7).

Electrical' connection is made to the antenna through a threaded nippleconnector 56 integrally formed on a skirt 12b which depends downwardlyfrom the lower edge of the base 12. This nipple connector 56 contains amale connector prong 58 which is supported at the central axis of theconnector and in insulated relation thereto by any annular spacer 60.'The prong 58 and the nipple 56 thus form a male coaxial connectoradapted for connection to a conventional female connector of a coaxialtransmission line which is used to conduct the signal picked up by theantenna to the radio receiver.V The male prong 5S ofthe connectorassembly is electrically connected to the fixed outer section 20 of theantenna through a capacitor 62, the pigtail leads of which arerespectively soldered to the outer section 20 and to the male prong S8.The nipple 56 and the integral body are grounded to the automobile bodythrough the toggle members 44 which have sharp projecting prongs attheir corners for piercing any undercoating on the automobile body andmaking good electrical contact with the body. This grounded connectionmay be augmented, if desired, by means of a terminal post 18aV('Figure 1) integrally formed at the lower side of the metal housing 18.

The lower end of the fixed outer section 20 of the whip is supported inthe extension tube 14 by means of an insulating spacer 64 which includesa central passageway lined with a tube 66 of insulating material throughwhich the liexible cable 38 passes. Secured to the lower end of theextension tube 14 by means of screws 68 is the neck 18a of the housing18 (see Figure 1).

Generally speaking, the housing 18 includes a tubular shell 70 (Figure2) which is closed at one end by an end plate 72 and at its other end bya cast plate 74 which has integrally formed thereon a shallow cup-likeportion 74a which receives and supports one end of the electric motor16. Extending across the shell 70 is an integral supporting wall 70awhich includes, at the central axis of the shell, a bearing sleeve 76which rotatably supports a drive shaft 78.

Secured at one end of this drive shaft 78 is a clutch assembly which isgenerally indicated 80 in Figure 2, and which is shown in greater detailin yFigure 3. As may be seen in the latter ligure, this clutch assemblyincludes a clutch plate 82, the hub portion 82a of which is keyed to thedrive shaft 78 by means of a pin 84 which is received in registeringlongitudinal slots formed in the outer surface of the shaft 78 and inthe inner surface of the hub 82a. The clutch plate 82 isV held on theend of the drive shaft 78 by means of a retainingrring 86 which isreceived in a peripheral slot 78a in the end of the drive shaft, with awasher 88 interposed between the retaining ring 86 and the outer end ofthe hub 82a. The face of the clutch plate 82 is provided with a seriesof spaced shallow indentations 8217 in which are partially received anequivalent number of ball bearings 90 which are interposed between theface of the clutchplate and the adjacent face of a spur gear 92 which issimilarly provided with shallow indentations to partially receive theball bearings 90. The gear 92 is resiliently urged toward the clutchplate 82 by means of a spring ,cup washer 94 (see also Figure 2) whichisvinterposed oetween the adjacent face of the gear 92 and a retainingring 96 which is received in a peripheral slot 78h in the drive shaft78.

When the gear 92 is driven, the drive shaft 78 is normally driven withvit through the clutch 80. However, when the resistance imposed upon thedrive shaft 78 reaches a predetermined level, the ball bearings 90 arecammed out of the indentations in the clutch plate 82 and/or the gear92, forcing these two members slightly apart against the resistance ofthe spring cup washer 94 and allowing relative rotation between them tocause the ball bearings 90 to move from their respective identations onone or both of these members into the adjacent indentations, thusallowing incremental slippage orfindexing of the clutch 80 so long asthe resistance continues, or until the driving power supplied to thegear 92 is cut olf. This arrangement thus limits the amount of drivingpower which can be supplied to the drive shaft 78.

The gear 92 is driven from the electric motor 16 through a pinion 98which is fixed on the shaft 100 of the motor 16. This pinion 98 engagesa spur gear 102 fixed on a shaft 104 which is journalled in the wall 70aand in the end plate 72 and on which is also xed pinion 106. This pinion106 meshes with a spur gear 108 fixed on a shaft 110 which is journalledin the wall 70a and in the end plate 72 and on which is also fixed apinion 112 which meshes with the gear 92. Thus, whenever the motor 16 isrunning, it drives the gear 92 at a reduced speed, and this gear in turndrives the drive shaft 78 through the clutch 80 except where theresistance imposed on the drive shaft 78 exceeds the level suicient tocause indexing -ofthe clutch 80,'as previously described.

Fixed on the end of the drive shaft 78 which projects through thesupporting wall 70u into the left-hand end of the housing 18, as viewedin Figure 2, is a cable-driv- -ing gear 114, the hub portion 116 ofwhich is formed of insulating material such as nylon, and the peripheralportion 117 of which is formed of a hard material such as steel. Theouter edge of the peripheral portion 117 is circumferentially grooved toreceive the cable 38 and is shaped to receive the teeth on the cable.The two portions 116 and 117 of the gear 114 are secured together byscrews 119. The gear 114 is rotatably received within a central chamber118 dened by a recess 120a in a guide member 120 and bythe cup-shapedcover plate 122. Both the guide member 120 and the cover plate 122 areformed of a plastic insulating material such as nylon, and they interlitwith one another to form a generally wafer-shaped assembly of an outsidediameter lslightly smaller than the inside diameter of the shell 70.

tion. It is just deep enough to admit the flexible cable 38 and is of adiameter just suicient to permit the flexi ble cable to be wrappedaround the periphery ofthe gear 114.without excessive friction betweenthe flexible cable 38 and the walls of the chamber '118. The guideassembly 120, 122 thus serves to maintain the flexible cable 38 indriving engagement with the gear 114. The guide member 120 is providedwith a vertical slot 120b which merges tangentially with the circularchamber 118 and through which the cable 38v passes into the chamber. Thecover plate 122 is provided with a notch 122a to provide clearance forthe cable.

As best shown in Figure S, the central chamber 118 is provided at oneside with'a spiral slot 126 which merges tangentially with the chamber118 and which extends from the chamber 118 on a path of graduallyincreasing radius of curvature. The depth of the slot 126 increases asthe slot progresses from the central chamber 118, so that the slotultimately extends through the opposite face of the guide member 120.The cover plate 122 is provided with a spiral ramp 128 (Figure 5) whichis adapted to be received inthe passageway 126 when the guide lmember120 and cover plate 122 are assembled. The outer surface of the ramp 128is spaced from the inner wall o f the passageway 126 by a uniformdista-nce suflicient to pass the flexible cable 38 so that the ramp 128and the passageway 126 together define a passageway for the flexiblecable 38 which, as previously mentioned, is on a gradually increasingradius of curvature, as well as being gradually dellected from 'theplane of the gear 114 toward the left, as viewed in Figures 2 and 5,until the liexible cable 38 passes completely through the guide member120.

Mounted at the left-hand side of the guide member 120, as viewed inFigures 2 and 5, is a reel 130, the hub portion 130a of which isrotatably supported on the drive shaft 78, with the reel 130 being heldon the end of the drive shaft 78 by a retaining ring 132 (Figure 2).

The reel 130 is provided with an outer generally cylindlical ange 130band an inner cylindrical flange 130e, both of which are coaxial with thereel and which are spaced apart to define an anular storage chamber1301i.

The edges of the flanges 1301) and 130e fit flush against the adjacentsurfaces lof the guide member 120 with the storage chamber 130d oppositethe opening in the guide member 120 through which the exible cablepasses.

When Ythe gear 114 is 'rotated by the motor 16 in a clockwise direction,as viewed in'sFi'gure'S.- itpulls'I the exible cable 38 downwardly fromthe upperportions of the antenna :assembly and pushes them through thevguide assembly 120, 122 into the storage chamber 130!! of the reel 130.Because the iiexible cable 38 resists bending, it -tends to engage theinner surface of the outer flange 130b of the reel 130, as shown inFigure 2. The inner surface of this outer ange 130b is slightly taperedi.e., its diameter at the input or right-hand end of the reel 130, asviewed in Figure 2, is slightly larger than its diameter atthe left-handend of the reel. Thus, lthe turns of the cable tend to remain near theinput or right-hand end of the reel until they are pushed farther intothe reel as additional turns lare added tothe store of cable 38 in thestorage chamber 1-30d.

Since the reel 130 is rotatable relative to the shaft 78, the reelrotates as the cable 38 is pushed into it or pulled from it so thatthere is little, if any, longitudinal movement of the cable 38 relativeto the surface or surfaces of the reel with which it is in engagement.This arrangement allows the cable 38 to be fed into or removed from thereel 38 without appreciable friction and without any substantial dangerof binding, kinking or jamming.

When the motor 16 is driven to rotate the gear 114 in a counterclockwisedirection, as viewed in Figure 5, the cable 38 is removed from the reel130 and is forced upwardly within the antenna structure, first to drivethe innermost section 26 of the lantenna upwardly to a fully extendedposition at which the ferrule 36 kengages the beading 32 near the upperend of the next adjacent outer section 24. Beyond this point, the innersection 26 carries the adjacent section 24 upwardly until it reaches afully extended position at which it carries the next outer section 22 upto its fully extended position. When this point is reached, the cable 38cannot move up any farther and the clutch 80 will index until the motor16 lis shut off. When the motor 16 is driven in the opposite directionthe cable 38 will be pulled down to return the antenna to the fullyretracted position in which it is shown in Figure 7, whereupon theclutch 80 will index unt-i1 the motor 16 is shut off.

Electrical control means are provided by which the motor 16 may beautomatically shut 0E after a number of revolutions at least suf`cientto drive the antenna all the way up or all the way down. Means are alsoprovided to cause the antenna, which is normally maintained in a fullyretracted position when the automobile radio is turned off, to be drivenautomatically to a partially extended position each time the automobileradio is turned on. From this position, the electric motor 16 may beenergized under manual control either to drive the antenna all the wayup or to return it to the partially extended position. Then, when theautomobile radio is turned od, the motor is automatically energized todrive the antenna to a fully retracted position.

This control means includes a switch-operating cam 134 (see particularlyFigure 4) fixed on a shaft 136 which is rotatably journalled in thesupporting wall 70a (Figure 2) and in the end plate 72. This cam 134 isprovided at Yits periphery with spur gear teeth.137 (see particularlyFigure 2) which are engaged by a pinion 13S (Figure 4) i'lxed on arotatably mounted shaft 140 on which is also fixed a spur gear 142. Thespur gear 142 meshes with a pinion 144 which is fixed on a rotatableshaft 146 on ywhich is also iixed a spur gear 148. The latter spur gearl148 meshes with the main gear 92 which is driven by the electric motor16 (Figure 2) as previously described. The ratio of gear reductionbetween the main gear 92 and the cam 134 is such that the cam 134 makesa little less than a full revolution each time the main gear 92 and thedrive gear 114 (Figure 2) make a number of revolutions sutlicient todrive the cable 38 from one extreme position of the antenna to the otherplus a safety margin to insure full movement of the antenna.

As best shown in Figures 8 and 9, the cam 134 cooperates with a switchgenerally indicated 150, having three sets of normally open,single-pole, single-throw contacts 152, 153 and 154. Asbest shown inFigure 9, the contacts 152 and 153 are arranged to cooperate withtheouter marginal portion 149 of the face of the cam 134, while thecontacts 154 are oiset (see Figure 8) so that they cooperate with anVelevated inner portion 151 of the cam 134.

In Figures 8 and 9 the cam 134 is shown in the position which itoccupies when theantenna is fully retracted. In this position, theswitch contacts 153 are in engagement with the surface 149 of the camand are held closed, and the switch contacts 154 are in engagement withthe elevated portion 151 of the cam 134 and are also closed. The switchcontacts 152 are opposite a cutout 155 inv the cam and are thereforeopen. This is the condition of the switch contacts during periods whenthe automobile radio is not in use.

Figure 6 shows the method of connection of the switch 150 in the circuitwhich controls the electric motor 16. The Amotor 16 has two eldwindings, one of which is energized to rotate the motor in the directionto drive the cable 38 up, and the other of which is energized to drivethe cable down. v The motor is provided with three leads 156, 158, and160 (Figure 6). The lead 156 is a common lead and is connected to oneterminal 162a of a source of direct current,such as an automobilestorage battery 162. The lead 158 of the motor connects with lthe eldwinding which is energized for driving the motor 16 in such direction asto drive the antenna downwardly. It is externally connected through thecontacts 152 of the cam-operated switch 150 to one of the Xed contacts164a of asingle-pole, double-throwswitch 164, which is mounted withinthe automobile radio and which is automatically actuated when theautomobile radio is turned on and oi, and is additionally connected toone of the xed contacts v166a of a manually operated, normally open,momentary Y contact single-pole, double-throw switch 166, which is usedfor manual control of the antenna position.

The lead 160 of the motor 116 connects to the ield winding which isenergized for driving the antenna upwardly. This lead isexternallyconnected through the contacts 153 of switch 150 to the other xedcontact 166b` of the manual control switch 166. This up lead 160 is alsoconnected through the other contacts 154 of the switch with the otherfixed contact 164b of the switch 164. The movable contacts 164e and 166eof the two switches 164 and 166 respectively are connected to the otherterminal 162b of the power source 162.

It thus may be seen that the common lead 156 of the motorg16 is alwaysconnected'v to one terminal of the power source, so that the motor willrotate in one direction or the other when the other terminal of thesource is connected to one of the leads 158 or 160.

Assume that the antenna is in its fully retracted position, with theswitchy contacts 153 and 154 closed as shown in Figure 8. When theautomobile radio is turned on, the switch 164 (Figure 6) is thrown fromthe position shown in full lines to the position shown in broken linesat which its movable contact 164e is in engagement with its xed contact164b. This connects the terminal 162b of the power source through theswitch 164 and through the closed contacts 154 of the switch 150 to theup lead of the motor 16. This causes the motor 16 to run in thedirection for driving the antenna upwardly.

When the antenna reaches a position approximately half-way between itsretracted and fully extended positions, the cam 134 (Figures 8 and 9)will have rotated to such position that the contacts of switch 150 willride oli the edge 15111 of the elevated portion 151 of the cam 134. Thiswill open the contacts 154 and break the circuit to the motor 16,causing the antenna to stop in a partially extended position. This isthe position in which the antenna is normally maintained vfor driving inareas local; to the stationbeing received-that is, in areas ofrelatively high signal strength.

y motor .16. This causes. the motorto run in such direction as lto drivethe, antenna` upwardly; Y When the antenna reaches its fully extendedposition, the clutch 80 (Figures 2 and 3) will index until the motor 16is shut olf. The motor will continue .to run untill the contacts 153 ofthe switch y150 ride off the edge 149e Aof the marginal portion 149 ofthe cam 135i, thereby opening the contacts 153 and breakingvthecircuitto themotor 16.

kWith the lantenna fully extended, if it is desired to lower the antennatov its partially extended position, themanual switch may be throwntothe down position, bringing its movable contact 166e into engagementwith its fixed contact 166e.. This completes the circuit from theterminal 162b, ofthe power sourcethrough vthe switch 166 and throughthe` now closed. contacts 152 of the switch 150 to the 'lead 1,5 8 ofthe motor 16. This causes the motor to rotate in such direction astodrive the antenna downjwardly.v When ythenrantenna reachesits fullyretracted position, the clutclrSl) ywill index until ythe motor 16 is,shut oli. A sthe motor continues to run, the contacts 152 \}ot;s,witch4 150 will ride off vthe edge 149 al of the marginal portion-149ofthe cam 134, opening the contacts V; 152, y,breaking thercircuit tothemotor 16 and shutting it However, -if Athe-:radio-is still onfa circuitwill be completed from the terminal V162b of the power source throughthe contacts 164e and.164b V of the radio switch 164 and` throughtheynowvclosed contacts V,154 of thel switch 15,0to the ftpflead 1,60 of .the motor 16.j This will cause the motor to run in such direction asto drive 'the antenna upwardly to its partially extended position,

as previously described, at-which point the contacts 154 .will ride ,oithe edge 151a of the cam 134, stopping the motor 16.

Whenever the radioiis turned of-, lthe switch 164 is l actuated to bring.its `movable contact 164C into engagev -mentwith its ixed contact 164e,as shown in full lines in Figure 6,` completing the circuit from theterminal 162b lof thepower source 162 through the switch contacts 164eand 164e and through, the closed contacts 152 of the switch 150V tol.the down lead 158 of the motor 16.

VThis will drive the motor in such directionas to lower the antennaruntil -it reaches itsfully retracted p osition and the motor is cut oifby the contacts 152 riding oli the edge 149b ot the cam 134. v k

It will thus be apparent that the present invention provides a practicalmechanism forl -controlling a motoractuated-whip-type antennafwhich isreliable in operation and relatively inexpensive in construction, andwhich is capable of both manually and automatically controlled movementto any ofseveral predeterminedl positions. i

It will therefore be appreciated that the aforementioned and otherdesirable objectives have been achieved. However, it should beemphasized that the particular embodiment of the invention which isshown and described herein is intended as merely illustrative ratherthan as restlictive of the invention.

I claim: Y

In an extensible automobile radio antenna of the type having a pluralityof telescoping sections of different diameter, and a mounting base forsupporting the outer section in insulated relation to the automobilebody, means for raising and' lowering said antenna comprising a exiblecable attached at its upper end to the innermost of said telescopingsect-ions, said cable having regularly spaced surface serrations adaptedto serve as rack teeth, a housing mounted at the lower end of said base,a drive gear in said housing, said drive gear having its peripheryshaped to interlit with said serrations of said cable, an electric motormounted on said housing, a slipping clutch connecting said motor to saiddrive gear, a rst electrical switch arranged to be actuated when theautomobile radio is turned on and 0E to connect said motor to a sourceof electrical current to cause it to drive said antenna upwardly whensaid radio is turned on and downwardly when it is turned oi, second,third and fourth electrica! switches mounted on said housing andconnected to control the supply of current from said source to saidmotor, a composite switch operating member mechanically coupled tosaidrdrive gear to be driven with it by said motor, said switchoperating member having switch operating surfaces cooperating with eachof said second, third and fourth switches, whereby to actuate saidsecond switch to stop said motor after said drive gear has made a uumherof rotations suiicient to drive said antenna up to a partially extendedposition,` to actuate said third switch to stop said motor after saiddrive gear has made an additional number of rotations at leastsuficientto drive said antenna up to a fully extended position, and to actuatesaid third switch to stop said motor aftersaid drive gear has made anumber of turns in the reverse `:direction at least suiiicient to drivesaid antenna down vto aretracted position, and a fifth, manuallyoperated swit'chlinte'rconnected with said second, third and fourthswitches wherebyl said motor can be connected to said source to 'bedriven in either direction under manual control. j Y

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